Characteristics of corrosion occurring in high tin bronzes and copper sulfide corrosion are discussed. The scanning electron microscope (SEM) with attached x-ray analyzer and other analytical techniques were used to examine corrosion products. It was shown that ghost metallic structure can be preserved in the corrosion layers. Another phenomenon occurs when corrosion leaves a surface rich in one metal, simulating a plated surface. See also AATA 19-956.